Appropriation is the idea that ate the art world. Go to any Chelsea gallery or international biennial and youíll find it. Itís there in paintings of photographs, photographs of advertising, sculpture with ready-made objects, videos using already-existing film. After its hothouse incubation in the Ď70s, appropriation breathed important new life into art. This life flowered spectacularly over the decades -- even if itís now close to esthetic kudzu.